The present invention refers to a micro-reactor system assembly comprising at least n process modules and at least n+1 heat exchange modules wherein each process module is sandwiched by two adjacent heat exchange modules.
Micro-reactors are reaction devices provided for reacting of one or more reactants (typically including mixing of two or more reactants) and to some extent for controlling the reaction of said reactants via heating or cooling or thermal buffering said reactants before, during and/or after mixing. Such micro-reactors for performing chemical reactions within small areas are known for example from EP-A-0688242, EP-A-1031375, WO-A-2004/045761 and US-A-2004/0109798.
Chemical reactions to be performed in micro-reactors can basically be distinguished between so-called type A reactions and type B reactions.
Type A as for example organic metal reactions are very fast chemical reactions and take place directly at mixing reactants within the mixing chamber, typically in the range of 1 sec. They may be called reactions controlled by the mixing process. In order to let all reactants react completely and to avoid by-products, such type A reactions require fast and effective mixing of the process fluids as well as effective thermal control. Such type A reactions generally require none or short after-reaction time and thus can be performed well in micro-reactors with small residence volume or after-reaction volume. The residence time for such reactions typically is in the range less than 20 sec.
Type B reactions as for example Wittig reactions or acetoacylation of an aromatic amine with diktene, on the contrary, are fast to slow reactions with typical reaction times in the range of 1 sec. to 10 min. They run concentration or kinetically controlled. In order to let the reactants react completely and to avoid by-products, such type B reactions do not require a very fast mixing of the reactants but rather controllable reaction conditions during the complete reaction time. Thus residence volume and after-reaction volume must be dimensioned such that the process fluid remains within the micro-reactor for a long time under conditions which can be controlled easily and precisely. However, until now realisation of such longer residence times is difficult with conventional micro-reactors due to the small sizes and the expensive micro-structuring. Thus conventional micro-reactors mostly are used for type A reactions.
It is therefore an object of the present invention to provide an improved micro-reactor system assembly suitable to assure desired residence times during which temperature control is possible.